Collision with terrain

A passenger on board the aircraft, said that the measured length of the airstrip was 1,000 m, with trees on the left and open grasslands on the right. He said the airstrip surface was rough to the left of the centreline for almost the entire length. The airstrip also had a slight uphill gradient in the take-off direction.

The passenger stated that he had taken a short flight with the pilot earlier the same day. He said that during the accident take-off the aircraft was further to the left of the runway centreline than on the previous occasion, and it appeared to accelerate more slowly. At a height of about 100 to 120 ft above ground level, the stall warning horn sounded, and the aircraft began to descend towards the trees to the left of the strip. The left wing then clipped a tree, and the aircraft descended to impact the ground nose first.

The investigator was unable to obtain details of the accident from the pilot in command.

The pilot reported that the landing was being conducted directly towards the setting sun. This affected his ability to see the strip and the aircraft touched down on the clearway beside the strip proper. During the landing roll, the nose wheel entered a depression which crossed the clearway and collapsed. Damage was also caused to both propellers and the forward underside of the fuselage.

The pilot reported that he had made an approach to land on runway 32. During the landing roll the pilot became concerned that the aircraft would not stop before the end of the runway, and he decided to go around for another circuit. The pilot applied power and attempted to fly the aircraft off the ground at the end of the runway. The aircraft did not climb, and the right wing collided with a three metre high tree causing the aircraft to slew around and touch down again. The right wing, engine cowl and nosewheel were also damaged as the aircraft came to a stop, still on its landing gear and pointing in the opposite direction to the landing, approximately 70 m from the end of the strip.

It is probable that the pilot flew the aircraft off the ground at too low an airspeed and the combination of the low airspeed and its associated drag prevented the aircraft from climbing clear of the obstacles.

The student had completed six circuits as part of a pre-second-solo check. The student's performance was accessed as satisfactory, by his instructor, and he was cleared to complete four solo circuits.

On the first solo circuit the aircraft ballooned during the landing flare. The aircraft was then observed to descend rapidly and land heavily on the main wheels after which, the nose came down starting a porposing action. The student applied full power to go-around but pitched the nose up too high (the student reported that the stall waring light and horn came on). The aircraft rolled to the left and descended impacting the ground initially with the left wing. The aircraft pitched nose first into the ground pivoting on the collapsed nosewheel in a clockwise direction whilst skidding away from the runway and coming to rest, upright, and facing the opposite direction to landing.

It is probable that the student's inexperience led to control mishandling which resulted in a stall and loss of control close to the ground.

When the pilot arrived over Toowoomba Aerodrome, he noted that the windsock favoured runway 29 and that the wind was strong. During late final approach he inadvertently allowed the speed to reduce too far, and a bounced, heavy landing resulted. He applied full power to go around but a strong wind gust from the south (mainly crosswind) moved the aircraft sideways. The aircraft failed to achieve flying speed and struck the ground, left wing and nose low. When the aircraft came to rest, its three occupants left the cabin without assistance. They were not injured. A very experienced local pilot had landed some 20 minutes earlier and he said that he had nearly lost control in the gusting crosswind. The hangars are known to generate strong vortices over the eastern threshold in strong south-westerly wind conditions.

The pilot reported that just prior to taking off during a spreading operation, a line squall had passed over the strip. Soon after becoming airborne the aircraft encountered an area of turbulence with associated sink, which it could not outclimb. Although the pilot attempted to dump the load of fertiliser to improve climb performance, the aircraft struck the ground in a level attitude and collided with a water pump, tearing the nose landing gear leg from the aircraft.

It was later determined that the fertiliser was damp, which adversely affected the dump capability of the aircraft.

The pilot was completing an approach to runway 10 at the time of the accident. The wind was reported as blowing from 060 degrees at 10-15 kts. At a height of approximately 30 ft the aircraft was observed to roll and yaw to the left of the runway centreline. In what appeared to be an attempted correction by the pilot, the aircraft was observed to roll and yaw to the right. At a height of approximately 15 ft, it was observed to turn back to the left and track, in a nose high attitude and with decreasing airspeed, towards trees to the north of the runway. The aircraft collided with the trees and came to a stop in a nose-down position.

The pilot reported that the atmospheric conditions were turbulent, with a crosswind and some wind shear evident during the approach. He had decided to use only 20 degrees of flap for the landing because of the conditions. At approximately 30 ft the aircraft was affected by a sudden wind gust which caused it to turn left and away from the runway. He tried to correct and applied power to commence a go-around, but the aircraft continued to descend. He retracted the flap in an attempt to improve the aircraft's performance, but this aggravated the situation. He was unable to prevent the collision.

The aircraft departed Griffith for a chemical spraying operation in the Hillston area. A considerable amount of fog and low cloud was encountered enroute, however, the pilot said he had been assured by the farmer at Hillston that the area was clear.

Nearing Hillston the pilot was unable to find a break in the cloud cover, so he elected to track to the east to find an opening but was unsuccessful. Shortly after commencing a return to Griffith the pilot said, he found a large cloud break. He notified his base of his intentions and descended below the cloud base. After passing over a low range of hills he descended to about 300 feet above ground level to continue to remain clear of cloud, but shortly after he was unable to prevent the aircraft from entering lower cloud.

The pilot commenced a slow turn, still able to see the ground immediately below the aircraft. However, he was unable to outclimb rising terrain, despite attempting to dump the chemical load. The aircraft consequently struck the ground and was destroyed, however, the pilot was able to vacate the aircraft without injury.

The pilot reported that while on approach to a three foot hover, he commenced a right turn to position the aircraft for refuelling. As he did so an unsecured object in the cockpit shifted, preventing movement of the cyclic control to the left. The pilot tried to recover the situation by increasing altitude, but the aircraft continued to roll right until the main rotor blades hit the ground. The aircraft was then thrown back onto its skids after which it rolled onto its left side.

The pilot reported that when the aircraft was about 300ft on final approach to runway 14, he noticed that the right engine rpm did not change as the propeller controls were set to fine pitch. The aircraft then yawed to the right when it became necessary to introduce power to avoid undershooting the runway.

Both propellers were selected to feather when the yawing moment became uncontrollable, at about 50ft AGL. The right wing struck the ground, the landing gear collapsed, and the right wing was torn off during the ground slide as the aircraft slide off the runway onto the grass flight strip. The two occupants were not injured and evacuated the aircraft unassisted.

Post flight inspection by a licenced aircraft maintenance engineer found that both propellers were on the coarse pitch stops and had not feathered.

Inspection of the suspect right engine failed to find a fault which could have contributed to a power loss.

The pilot was under the impression that he had feather both propellers when he experienced directional control difficulties. Examination of both propeller hubs found that the propeller blades were on the coarse pitch stops. The propeller pitch control levers require a distinct movement to pass the coarse pitch stops into the feather position. It is apparent that the pilot did not position the levers where he intended.

The pilot lost control of the aircraft on late final approach. The reason for the loss of control could not be determined from the evidence available.